PROJECT SUMMARY/ABSTRACT Mount Sinai will partner with the National Institute of Public Health, Mexico and Columbia University to continue to follow 700 children at ages 8-11 in the PROGRESS birth cohort established in 2006 in Mexico City to study perinatal programming of child development. PROGRESS is a state of the art birth cohort that has developed innovative new methods to estimate past exposure to environmental chemicals, both with biomarkers of internal dose (e.g. teeth based chemical assays) and with geospatial modeling of the external environment via remote sensing(e.g. air pollution, green space etc). This application will also leverage Mount Sinai's recently established Environmental Health Sciences Laboratory to build upon our internationally recognized research expertise in children's environmental health. Our mission is to measure environmental exposures across pregnancy and childhood to determine how these factors affect neurodevelopment and growth. We are especially excited to extend this work in PROGRESS as our overarching goal is to prepare the cohort the coming era of exposomic research. In this R24 we will test methods for data harmonization that will be critical to future work. By piloting pooling methods with researchers with similarly designed cohorts we set the stage to build new consortia to study the health impacts of chemicals, nutrition, social factors, and the gene-environment interactions that underlie childhood disease. Our team has all the requisite expertise in exposure science, biostatistics, child health phenotyping and in cohort management. We have already developed several new methodologies to objectively reconstruct past chemical exposures that precisely estimate exposure timing, allowing researchers to identify susceptibility windows as they relate to child health. Over the last 10 years, PROGRESS has supported 16 NIH grants led by 10 different researchers (including 7 K awardees), demonstrating our ability to serve as an incubator for the next generation of Environmental Health scientists. To accommodate divergent research needs among this group, the PI has formed the equivalent of an Administrative Core that will plan, organize, streamline and prioritize field work by coordinating the associated administrative work (IRB, protocol development, finances etc). We will also develop new programs to assess participant needs in order to improve retention, adapt to advances in social media, assess new health outcomes and exposures, and implement new exposure/response assays as we prepare our cohort for future big data consortia research. This proposal links highly experienced environmental health scientists with statisticians, social epidemiologists, child psychologists, chemists, pediatricians, and epigeneticists to support the infrastructure of a highly functional, state of the longitudinal birth cohort that objectively measures the human environments that program child health. We will follow PROGRESS children up to the onset of puberty, linking fetal exposures to health changes inherent to this critical life stage. Finally, despite our many successes, without this R24, field work will cease and this application is critical to our future success.